DE102009034798A1 - Rolling bearings, in particular single row deep groove ball bearings for a dual mass flywheel in a motor vehicle - Google Patents

Abstract

The invention relates to a roller bearing (5) in the form of a single row deep groove ball bearing, which essentially consists of an inner bearing ring (6) and an outer bearing ring (7) arranged coaxially therewith as well as a plurality of bearing balls (6, 7) arranged between these bearing rings (6, 7). 8), which roll in groove-shaped raceways (9, 10) in the outer circumferential surface (11) of the inner bearing ring (6) and in the inner circumferential surface (12) of the outer bearing ring (7) and through a bearing cage (13) in the circumferential direction in uniform Distances are kept from each other, wherein the interior (14) of the roller bearing (5) is sealed by two axially opposite annular seals (15, 16) and has a lifetime filling with a roller bearing lubricant. According to the invention, at least one of the two seals (15, 16) is designed as an angular profile-shaped lip seal (17), the dimensionally stable radial sealing leg (18) of which is fastened to the outer bearing ring (7) and a gap seal (19) of the inner bearing ring (6). 20) is arranged forming and the resilient axial sealing lip (21) of the inner bearing ring (6) engages under the inner bearing ring (6) and rests against its inner lateral surface (22) and is at the same time designed as a pressure relief valve.

Description

Field of the invention

The The invention relates to a single-row deep groove ball bearing Rolling bearings according to the preamble forming features of Patent claim 1, which is particularly advantageous for storage the secondary mass on the primary mass of a dual-mass flywheel is applicable in a motor vehicle.

Background of the invention

As is known, are dual mass flywheels between the engine and arranged the transmission of a motor vehicle and to increase the ride comfort provided. Such a dual mass flywheel exists essentially from a directly with the crankshaft of the internal combustion engine connected disc-shaped primary mass and out a coaxial with this primary mass arranged disc-shaped Secondary mass via a coupling with the Input shaft of the transmission is connected.

Both Masses are by several arranged between these damping means in the form of usually two opposite ones, curved spiral compression springs coupled together and against the Effect of these damping means on one on one Bearing flange arranged on the primary mass friction reducing Storage rotatable relative to each other. During operation of the motor vehicle is about the rotating crankshaft of the engine the primary mass is actively driven while over the damping elements in turn, the transmission input shaft driving secondary mass is taken. about The damping elements are on the one hand from imbalances the moving masses in the drive train resulting in unevenness and on the other hand, the rotational irregularities resulting from the piston movements steamed of the internal combustion engine.

Since the storage between the secondary mass and the primary mass of the dual mass flywheel is subject to a particularly high wear, especially due to the influence of temperature from the clutch ago, this is usually formed by special deep groove ball bearings in the form of so-called DFC bearings, as for example from DE 42 14 655 A1 and from the DE 196 31 725 A1 are known. These deep groove ball bearings are known to consist of an inner bearing ring and an outer bearing ring and a plurality of bearing rings arranged between these bearing balls, which roll in groove-shaped raceways in the outer circumferential surface of the inner bearing ring and in the inner circumferential surface of the outer bearing ring and by a bearing cage in the circumferential direction at regular intervals held each other. Since there are no regreasing options for deep groove ball bearings in dual-mass flywheels, their lifetime depends on the size of the existing lubricant reservoir. For filling the interior of these deep groove ball bearings with sufficient for their entire life lubricant quantity therefore have on one side special plastic sealing caps on the outer bearing ring and the inner bearing ring over and under and are formed with an additional axial cavity through which the volume of the warehouse interior is increased many times over.

such Plastic sealing caps on the deep groove ball bearings of dual mass flywheels However, they are relatively expensive to manufacture and delicate in the bearing assembly and have in practice also to the effect proved to be disadvantageous that their grinding on the inner surface of the inner bearing ring fitting sealing collar a high bias and has a relatively low elasticity, by the a high friction torque between this and the inner bearing ring is created. This high friction torque is the cause of almost complete premature wear of this Sealing collar, leaving it behind by the lack of overlap this sealing area to lubricant leaks on the adjacent sealing gap between the plastic sealing cap and the inner bearing ring and a shortening of the service life the deep groove ball bearing comes.

To avoid these disadvantages was therefore not yet published by the date of filing the present patent application German patent application with the official file number 10 2008 048 517.9 a rolling bearing for a dual-mass flywheel proposed, which has substantially the same structure as the previously described deep groove ball bearings, but is designed with a deviating from the standard dimensions far greater axial width to obtain a sufficient for a lifetime filling with lubricant volume of the interior space between the bearing rings , The interior of the rolling bearing is sealed by two axially opposite and trained as a metal-reinforced lip seals annular seals which are snapped on the one hand in a retaining groove in the inner circumferential surface of the outer bearing ring and on the other hand each have two abrading on the outer circumferential surface of the inner bearing ring sealing lips. In addition, several small vent holes are in these seals in height of the bearing subcircuit incorporated, over which the roller bearing in case of exceeding a resulting at higher temperatures by outgassing of the filled lubricant allowable gas pressure in the interior of which is forced ventilation.

adversely in these seals for deep groove ball bearings of dual mass flywheels is, however, that the vent holes only by consuming Laser drilling can be introduced and thus the purchase a correspondingly expensive laser drilling device and matching recording tools provide. Similarly, laser drilling requires additional additional Working steps such as cleaning the sealing rings after lasing the ventilation holes and a visual inspection, so that the manufacturing cost of such seals are in uneconomical Move areas. In addition, it has been proven in practice that Such vent holes to clogging due to contamination or by resinification of the lubricant tend, so they the can no longer fulfill their intended function and it when exceeding the permissible gas pressure in the interior of the bearing for squeezing the lubricant over the elastic sealing lips of the sealing rings as well as also to one Life shortening of the deep groove ball bearing comes.

Object of the invention

outgoing from the stated disadvantages of the known prior art Therefore, the invention is based on the object, a roller bearing, in particular single row deep groove ball bearing for a dual mass flywheel, to design, which with wear-resistant and cost-effective producible seals is provided, which is also a reliable Venting of the rolling bearing when exceeded ensure a permissible gas pressure in its interior.

Description of the invention

According to the invention this task in a rolling bearing according to the preamble of claim 1 solved such that at least one of Both seals as angular profile lip seal is formed, the dimensionally stable radial sealing leg on the outside Bearing ring attached and with an axial side of the inner bearing ring a gap seal is arranged forming and their resilient Axial sealing lip grinding under the inner bearing ring arranged adjacent to the inner circumferential surface and at the same time is designed as a pressure relief valve, through which the Rolling bearings when a permissible limit is exceeded Gas pressure in the interior of the gap seal and over at least locally from the inner surface of the inner bearing ring lifting sealing lip forced ventilation is.

preferred Embodiments and advantageous developments of the invention formed Rolling bearing are described in the subclaims.

After that it is according to claim 2 in the inventively designed Rolling provided, that preferably only the secondary mass side seal is designed as an angle profile-shaped lip seal, while the primary mass side seal through a lip seal ring known per se is formed, on the one hand in a retaining groove in the inner circumferential surface of the outer Bearing ring is snapped and on the other hand, two on the outer circumferential surface having the inner bearing ring abrading fitting sealing lips. Such a seal pairing has proven to be particularly cost-effective and as functionally sufficient, since the known lip seals an optimal seal against the escape of lubricant offer the camp and at the same time the entry of contaminants Avoid the nearby clutch bell in the bearing. Conceivable but it would be, both seals of the bearing form as angular profile lip seals.

To Claim 3, it is a further feature of the invention formed Rolling that the radial sealing leg of the angle-profile Lip seal is stiffened by a metal reinforcement and with its free edge part in another circumferential receiving groove in the inner circumferential surface of the outer Bearing ring is snapped. The metal reinforcement ensures the radial stiffness of the otherwise made of a vulcanized elastomer Lip seal and ensures that the axial side formed the inner bearing ring gap seal a uniform Has gap.

According to claim 4, the inventively designed roller bearing is also characterized by the fact that the inner bearing ring relative to the outer bearing ring has a reduced by the thickness of the radial sealing leg of the lip seal and the gap of the gap seal axial width. This ensures that the rolling bearing has a consistently uniform axial width with inserted lip seal. In addition, the inner bearing ring is formed with an approximately to the length of the axial sealing lip of the lip seal reduced bearing seat width on the inner circumferential surface to provide the necessary space requirements for the axial sealing lip. The standing in sliding contact with the axial sealing lip part of the inner circumferential surface of the inner bearing ring can either have the same diameter as the bearing seat, so that the bearing flange on the Primary mass is formed with a thickness of this sealing lip corresponding undercut, or the inner circumferential surface of the inner bearing ring is provided with such a stepped undercut, so that when inserted Lip-pendichtung the bottom of the axial sealing lip has approximately the same level as the bearing seat.

A expedient development of the invention formed Rolling it is according to claim 5 further, that the with the axial sealing lip of the lip seal in sliding contact standing part of the inner circumferential surface of the inner bearing ring additionally with a circumferential groove and one to the axial side of the inner bearing ring extending chamfer is thus formed the friction surface of the axial sealing lip on the inner bearing ring to reduce. Formed between the circumferential groove and the chamfer thus an approximately wedge-shaped ring contour on the inner circumferential surface of the inner race on which the axial lip of the lip seal only via a low-friction line contact to the inner Bearing ring is applied. The elasticity of the axial sealing lip and unavoidable leaking over the gap seal Lubricant leaks also ensure that that the axial sealing lip over the life of the rolling bearing has almost no wear.

After all It is designed as an advantageous variant of the invention Rolling bearing by the claims 6 and 7 nor suggested that the lip seal on the inside of its radial sealing leg has an additional pre-seal lip and that in the Outer shell surface of the inner bearing ring directly in front of the pre-lip of the lip seal an additional Slip groove is incorporated. The additional pre-seal lip has while an approximately pent roof-shaped profile cross-section and should avoid that during storage downtime liquid or low-viscosity lubricant directly into the gap seal between this and the axial side of the inner bearing ring can drain. The centrifugal groove in the outer surface of the In contrast, the inner bearing ring preferably has a semicircular profile cross section and forms a trailing edge in the warehouse, the centrifugal force To avoid creeping of the lubricant in the gap seal. additionally On the other hand, such a centrifugal groove can also occur immediately before the primary-mass-side lip sealing ring in the outer circumferential surface be incorporated in the inner bearing ring, even on this Side of the camp a trailing edge against centrifugal creep of the lubricant to form under the sealing lips.

In summary has the inventively designed deep groove ball bearings for a dual mass flywheel thus compared to the Deep groove ball bearings known from the prior art have the advantage on that it is at the same time designed as a pressure relief valve Has lip seal, despite sliding contact with the inner bearing ring is almost wear-free due to the elasticity of its axial sealing lip and by locally lifting off the inner circumferential surface the inner bearing ring a reliable vent of the rolling bearing when a permissible limit is exceeded Guaranteed gas pressure in the interior. This can at the same time a complex introduction of individual blockages threatened vent holes omitted, leaving the lip seal overall extremely inexpensive to produce is. In addition, there is the possibility through different dimensions of the axial sealing lip of the lip seal the permissible gas pressure in the interior of the rolling bearing limit accordingly in height. Likewise, the Lip seal easy and safe on rolling bearings without the Risk of inversion of sealing lips are mounted and made possible by their external visibility at the same time a safe and correct mounting of the rolling bearing in the dual mass flywheel.

Brief description of the drawings

A preferred embodiment of the invention formed Rolling bearing is described below with reference to the accompanying Drawings explained in more detail. Showing:

1 a cross section through a dual mass flywheel with a rolling bearing designed according to the invention;

2 an enlarged overall view of an inventively designed roller bearing;

3 an enlarged view of the detail X of the inventively designed roller bearing according to 2 ;

4 an enlarged view of the detail X according to 2 with a variant of the invention designed rolling bearing.

Detailed description the drawings

Out 1 is a schematic representation of a dual mass flywheel 1 for a motor vehicle, which essentially consists of a disc-shaped primary mass connected directly to the crankshaft of the internal combustion engine 2 and from a coaxial to this primary mass 2 arranged disc-shaped secondary mass 3 exists, which is connected via a coupling with the input shaft of the transmission. Both masses 2 . 3 are coupled together by a plurality of damping means arranged between them, but not shown together and against the action of these damping means via a on a bearing flange 4 on the primary mass 2 arranged rolling bearing 5 rotatable relative to each other.

By 2 is further clear that in the dual mass flywheel 1 arranged rolling bearings 5 essentially from an inner bearing ring 6 and from a coaxial with this outer bearing ring 7 and a variety between these bearing rings 6 . 7 arranged bearing balls 8th that exists in grooved tracks 9 . 10 in the outer circumferential surface 11 of the inner bearing ring 6 and in the inner circumferential surface 12 of the outer bearing ring 7 unroll and through a storage cage 13 be held in the circumferential direction at regular intervals to each other. The interior 14 of the rolling bearing 5 is by two axially opposite annular seals 15 . 16 sealed and completely filled with a rolling bearing lubricant, not shown, the amount of which is designed for the entire bearing life.

Out 3 Moreover, it is clear that the secondary-mass side seal 16 according to the invention as an angle-profile lip seal 17 is formed, the dimensionally stable radial sealing leg 18 on the outer bearing ring 7 attached as well as with an axial side 19 of the inner bearing ring 6 a gap seal 20 forms and their resilient axial sealing lip 21 the inner bearing ring 6 engages and rubs against its inner surface 22 is applied. The axial sealing lip 21 is at the same time designed as a pressure relief valve, through which the rolling bearing 5 when a permissible gas pressure resulting from outgassing of the filled lubricant is exceeded in its interior 14 over the gap seal 20 forcibly vented by the sealing lip 21 at least locally from the inner circumferential surface 22 of the inner bearing ring 6 takes off. The primary mass side seal 15 On the other hand, it is clearly visible as a lip seal known per se, which is formed in a circumferential receiving groove 23 in the inner circumferential surface 12 of the outer bearing ring 7 is held.

Furthermore goes out 3 show that the radial sealing leg 18 the angle profile shaped lip seal 17 through a metal reinforcement 24 is stiffened and with its free edge 25 in another circumferential receiving groove 26 in the inner circumferential surface 12 of the outer bearing ring 7 is snapped. The metal reinforcement 24 ensures the radial stiffness of the otherwise made of a vulcanized elastomer lip seal 17 and ensures that the to the axial side 19 of the inner bearing ring 6 formed gap seal 20 has a uniform gap.

Likewise is in 3 to see that the inner bearing ring 6 opposite the outer bearing ring 7 about the thickness of the radial sealing leg 18 the lip seal 17 reduced axial width and about the length of the axial sealing lip 21 reduced bearing seat width on the inner circumferential surface 22 having. The one with the axial sealing lip 21 in sliding contact part of the inner circumferential surface 22 of the inner bearing ring 6 has the same diameter as its unspecified bearing seat, so that the bearing flange 4 on the primary mass 2 , as in 1 indicated with one of the thickness of this sealing lip 21 corresponding undercut is formed.

Finally, in 3 still recognizable that with the axial sealing lip 21 the lip seal 17 in sliding contact part of the inner circumferential surface 22 of the inner bearing ring 6 additionally with a circumferential groove 27 and one to the axial side 19 of the inner bearing ring 6 running bevel 28 is formed, so as to the friction surface of the axial sealing lip 21 on the inner bearing ring 6 to reduce. Between the circumferential groove 27 and the chamfer 28 thus creates an approximately wedge-shaped ring contour on the inner surface 22 of the inner bearing ring 6 at the axial sealing lip 21 the lip seal 17 only via a low-friction line contact to the inner bearing ring 6 is applied.

In 4 In addition, is still an advantageous variant of the invention designed rolling bearing 5 shown, both the lip seal 17 on the inside of its radial sealing leg 18 an additional pre-seal lip 29 with pent roof-shaped profile cross-section, with which in case of storage downtime a direct dripping liquid lubricant in the gap seal 20 between this and the axial side 19 of the inner bearing ring 6 is avoidable. In addition, in this variant in the outer circumferential surface 11 of the inner bearing ring 6 immediately in front of the pre-seal lip 29 the lip seal 17 one more spin 30 incorporated with a semi-circular profile cross-section, which in the bearing operation a trailing edge against centrifugal force in the gap seal 20 forms creeping lubricant.

LIST OF REFERENCE NUMBERS

1

Dual Mass Flywheel

2

primary mass

3

secondary mass

4

Lagerflansch at 2

5

roller bearing

6

internal bearing ring

7

outer bearing ring

8th

bearing balls

9

career in 6

10

career in 7

11

Outer casing surface from 6

12

Inner surface area from 7

13

bearing cage

14

inner space of 5

15

poetry

16

poetry

17

lip seal

18

radially Sealing leg of 17

19

axial from 6

20

gap seals

21

axial Sealing lip of 17

22

Inner surface area from 6

23

receiving groove in 12

24

metal reinforcement from 18

25

edge part from 18

26

receiving groove in 12

27

groove in 22

28

chamfer at 22

29

Vordichtlippe at 18

30

Schleudernut in 11

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 4214655 A1 [0004]
• - DE 19631725 A1 [0004]
• - DE 102008048517 [0006]

Claims (7)

Rolling bearings, in particular single row deep groove ball bearings for a dual mass flywheel ( 1 ) in a motor vehicle, which rolling bearings ( 5 ) essentially of an inner bearing ring ( 6 ) and from a coaxial with this outer bearing ring ( 7 ) and a plurality between these bearing rings ( 6 . 7 ) arranged bearing balls ( 8th ) in grooved tracks ( 9 . 10 ) in the outer circumferential surface ( 11 ) of the inner bearing ring ( 6 ) and in the inner circumferential surface ( 12 ) of the outer bearing ring ( 7 ) and through a bearing cage ( 13 ) are kept at equal intervals in the circumferential direction, wherein the interior ( 14 ) of the rolling bearing ( 5 ) by two axially opposite annular seals ( 15 . 16 ) and has a life-time filling with a roller bearing lubricant, characterized in that at least one of the two seals ( 15 . 16 ) as angle-profile-shaped lip seal ( 17 ) is formed whose dimensionally stable radial sealing leg ( 18 ) on the outer bearing ring ( 7 ) and with an axial side ( 19 ) of the inner bearing ring ( 6 ) a gap seal ( 20 ) is arranged forming and whose resilient axial sealing lip ( 21 ) the inner bearing ring ( 6 ) under cross grinding on the inner circumferential surface ( 22 ) arranged adjacent and at the same time designed as a pressure relief valve, through which the rolling bearing ( 5 ) when a permissible gas pressure in its interior space is exceeded ( 14 ) over the gap seal ( 20 ) as well as over at least locally from the inner circumferential surface ( 22 ) of the inner bearing ring ( 6 ) lifting lip ( 21 ) is forced ventilation. Rolling bearing according to claim 1, characterized in that preferably only the secondary mass side seal ( 16 ) as angle-profile-shaped lip seal ( 17 ) is formed while the primary mass side seal ( 15 ) by a in a circumferential receiving groove ( 23 ) in the inner circumferential surface ( 12 ) of the outer bearing ring ( 7 ) held lip seal is formed. Rolling bearing according to claim 2, characterized in that the radial sealing leg ( 18 ) of the angle profile-shaped lip seal ( 17 ) by a metal reinforcement ( 24 ) is stiffened and with its free edge ( 25 ) in a further circumferential receiving groove ( 26 ) in the inner circumferential surface ( 12 ) of the outer bearing ring ( 7 ) can be snapped. Rolling bearing according to claim 2, characterized in that the inner bearing ring ( 6 ) relative to the outer bearing ring ( 7 ) about the thickness of the radial sealing leg ( 18 ) of the lip seal ( 17 ) reduced axial width and about the length of the axial sealing lip ( 21 ) reduced bearing seat width on the inner circumferential surface ( 22 ) having. Rolling bearing according to claim 4, characterized in that the with the axial sealing lip ( 21 ) of the lip seal ( 17 ) in sliding contact part of the inner circumferential surface ( 22 ) of the inner bearing ring ( 6 ) by a circumferential groove ( 27 ) and through to the axial side ( 19 ) of the inner bearing ring ( 6 ) running bevel ( 28 ) is reduced friction in its width. Rolling bearing according to claim 5, characterized in that the lip seal ( 17 ) on the inside of its radial sealing leg ( 18 ) an additional pre-seal lip ( 29 ), with which in case of standstill direct dripping liquid lubricant in the gap seal ( 20 ) between this and the axial side ( 19 ) of the inner bearing ring ( 6 ) is avoidable. Rolling bearing according to claim 6, characterized in that in the outer circumferential surface ( 11 ) of the inner bearing ring ( 6 ) immediately in front of the pre-seal lip ( 29 ) of the lip seal ( 17 ) an additional centrifugal groove ( 30 ) is incorporated, which in the bearing operation a trailing edge against centrifugal force in the gap seal ( 20 ) forms creeping lubricant.

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